1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <stdio.h> 18 #include <stdlib.h> 19 #include <fcntl.h> 20 #include <unistd.h> 21 #include <errno.h> 22 #include <string.h> 23 #include <dirent.h> 24 #include <errno.h> 25 #include <fcntl.h> 26 #include <vector> 27 #include <string> 28 29 #include <sys/types.h> 30 #include <sys/stat.h> 31 #include <sys/types.h> 32 #include <sys/mman.h> 33 #include <sys/mount.h> 34 #include <sys/wait.h> 35 36 #include <linux/kdev_t.h> 37 38 #define LOG_TAG "Vold" 39 40 #include <android-base/logging.h> 41 #include <android-base/stringprintf.h> 42 #include <cutils/log.h> 43 #include <cutils/properties.h> 44 #include <logwrap/logwrap.h> 45 #include <selinux/selinux.h> 46 47 #include "Ext4.h" 48 #include "Utils.h" 49 #include "VoldUtil.h" 50 51 using android::base::StringPrintf; 52 53 namespace android { 54 namespace vold { 55 namespace ext4 { 56 57 static const char* kResizefsPath = "/system/bin/resize2fs"; 58 static const char* kMkfsPath = "/system/bin/make_ext4fs"; 59 static const char* kFsckPath = "/system/bin/e2fsck"; 60 61 bool IsSupported() { 62 return access(kMkfsPath, X_OK) == 0 63 && access(kFsckPath, X_OK) == 0 64 && IsFilesystemSupported("ext4"); 65 } 66 67 status_t Check(const std::string& source, const std::string& target) { 68 // The following is shamelessly borrowed from fs_mgr.c, so it should be 69 // kept in sync with any changes over there. 70 71 const char* c_source = source.c_str(); 72 const char* c_target = target.c_str(); 73 74 int status; 75 int ret; 76 long tmpmnt_flags = MS_NOATIME | MS_NOEXEC | MS_NOSUID; 77 char *tmpmnt_opts = (char*) "nomblk_io_submit,errors=remount-ro"; 78 79 /* 80 * First try to mount and unmount the filesystem. We do this because 81 * the kernel is more efficient than e2fsck in running the journal and 82 * processing orphaned inodes, and on at least one device with a 83 * performance issue in the emmc firmware, it can take e2fsck 2.5 minutes 84 * to do what the kernel does in about a second. 85 * 86 * After mounting and unmounting the filesystem, run e2fsck, and if an 87 * error is recorded in the filesystem superblock, e2fsck will do a full 88 * check. Otherwise, it does nothing. If the kernel cannot mount the 89 * filesytsem due to an error, e2fsck is still run to do a full check 90 * fix the filesystem. 91 */ 92 ret = mount(c_source, c_target, "ext4", tmpmnt_flags, tmpmnt_opts); 93 if (!ret) { 94 int i; 95 for (i = 0; i < 5; i++) { 96 // Try to umount 5 times before continuing on. 97 // Should we try rebooting if all attempts fail? 98 int result = umount(c_target); 99 if (result == 0) { 100 break; 101 } 102 ALOGW("%s(): umount(%s)=%d: %s\n", __func__, c_target, result, strerror(errno)); 103 sleep(1); 104 } 105 } 106 107 /* 108 * Some system images do not have e2fsck for licensing reasons 109 * (e.g. recent SDK system images). Detect these and skip the check. 110 */ 111 if (access(kFsckPath, X_OK)) { 112 ALOGD("Not running %s on %s (executable not in system image)\n", 113 kFsckPath, c_source); 114 } else { 115 ALOGD("Running %s on %s\n", kFsckPath, c_source); 116 117 std::vector<std::string> cmd; 118 cmd.push_back(kFsckPath); 119 cmd.push_back("-y"); 120 cmd.push_back(c_source); 121 122 // ext4 devices are currently always trusted 123 return ForkExecvp(cmd, sFsckContext); 124 } 125 126 return 0; 127 } 128 129 status_t Mount(const std::string& source, const std::string& target, bool ro, 130 bool remount, bool executable) { 131 int rc; 132 unsigned long flags; 133 134 const char* c_source = source.c_str(); 135 const char* c_target = target.c_str(); 136 137 flags = MS_NOATIME | MS_NODEV | MS_NOSUID | MS_DIRSYNC; 138 139 flags |= (executable ? 0 : MS_NOEXEC); 140 flags |= (ro ? MS_RDONLY : 0); 141 flags |= (remount ? MS_REMOUNT : 0); 142 143 rc = mount(c_source, c_target, "ext4", flags, NULL); 144 145 if (rc && errno == EROFS) { 146 SLOGE("%s appears to be a read only filesystem - retrying mount RO", c_source); 147 flags |= MS_RDONLY; 148 rc = mount(c_source, c_target, "ext4", flags, NULL); 149 } 150 151 return rc; 152 } 153 154 status_t Resize(const std::string& source, unsigned long numSectors) { 155 std::vector<std::string> cmd; 156 cmd.push_back(kResizefsPath); 157 cmd.push_back("-f"); 158 cmd.push_back(source); 159 cmd.push_back(StringPrintf("%lu", numSectors)); 160 161 return ForkExecvp(cmd); 162 } 163 164 status_t Format(const std::string& source, unsigned long numSectors, 165 const std::string& target) { 166 std::vector<std::string> cmd; 167 cmd.push_back(kMkfsPath); 168 cmd.push_back("-J"); 169 170 cmd.push_back("-a"); 171 cmd.push_back(target); 172 173 if (numSectors) { 174 cmd.push_back("-l"); 175 cmd.push_back(StringPrintf("%lu", numSectors * 512)); 176 } 177 178 // Always generate a real UUID 179 cmd.push_back("-u"); 180 cmd.push_back(source); 181 182 return ForkExecvp(cmd); 183 } 184 185 } // namespace ext4 186 } // namespace vold 187 } // namespace android 188
